Preheat the oven to 160C. Tip the pasta and cavolo nero into a pan of salted boiling water. Cook until al dente, drain, and tip into a baking dish.

Place a frying pan over medium heat and heat the oil. Add the garlic and onion with a pinch of sea salt. After 2-3 minutes, add the chilli flakes, fennel seeds and sausage, and cook while stirring until the sausage has browned, about 5 minutes.

Add the sausage mixture to the pasta and cavolo nero and stir together. Top with dollops of ricotta and scatter with parmesan. Bake for 10-15 minutes until golden and oozy.